Loud-speaker



Feb. 4, 1930. L. M. CLEMENT LOUD SPEAKER Filed Sept. 11. 1926 2 Sheets-Shee l Feb. 4, 1930. CLEMENT 1,745,405

LOUD SPEAKER Filed Sept. 11. 1926 2. Sheets-Shee 2 Patented Feb. 4 1930 'UZWTED STATES PAT T FFIQ ;-1

LEWIS M. CLEMENT, 0F MOUNTAIN LAKES, NEW JERSEY, ASSIGNOR T9 A. D. ANDREA, INCL, 0F NEW YORK, N. Y., A CORPORATION OF NEW YUBK LOUD-SEEAYKER Application filed iteptember 11, 1926. Serial No. 134,780.

My invention relates to sound reproducing means, and particularly to such means generally known as loud speakers. My invention relates more specifically to a loud speaker of the sound radiator type as distinguished "from the sound box and horn type.

My invention will be better understood by reading the following description in connection with the attached drawings illustrating one embodiment of my invention, and in which:

Fig. 1 is a front elevation of the device;

Fig. 2 is a rear elevation of the device;

Fig. 3 is a vertical section on lines IIIIII of Figs. 1 and 2;

Fig. i is a section on line IVTV of Fig. 3 and I Fig. 5 is a fragmentary sectional view of the apex of the sound radiator on a scale larger than that of the other figures.

Referring to the drawings, the device consists of a stand 1 of any desired construction and configuration. The stand illustrated has five supports 2, attached to the standby screws, or they may be integral with the stand. The stand also has a ring shaped member 3 with two parallel bars 4 and a handle 5.

An actuating unit, later described, is supported by the bars 4.

The supports 2 are provided at their outer endswith theaded openings. A sound radiator 6 is held in place by screws 7 which pass through openings in flexible supporting members 8 which are fastened over openings in the sound radiator board6 as shown in detail in Fig. 3. The members 8 may be of any suitable material, such as leather. These members are quite flexible in a direction transverse to the plane of the sound radiator, but are relatively inflexible in a direction parallel with the plane of the sound radiator. The screws 7 pass through the members 8 substantially normal to the surface of the sound radiator. As illustrated, the supports 2 are arranged in a circle, but they may be located otherwise than in a circle. In fact I prefer to locate the supports in non-circular 'ositions, as it prevents localized vibrations in the sound radiator. By supporting the sound radiator at points at difiering dis- 'tances from the apex of the member A, a

an edging oftape or braid 9. The manufacture of the sound radiator is facilitated by laying the portion B flat against the portion A while the bases are stitched. They can be moved to the relative positions shown in Fig. 3 after the stitching is completed. The sound radiator ma be made of any suitable material, but I pre 'er fairly heavy paper. The stitchin of'the sound radiator around the edges a ds greatly to its strength and durability. This construction eliminates the cementing heretofore used in devices of this type and which has been a source otweakness thereof.

I also prefer to stifien the sound radiator so as to avoid localized vibration. In the drawings, 1 have illustrated two forms of stifiening means. One of these consists of light angle sections 40 spaced around the back face of the cone section A. They preferably are located outside the supports 2 and on'radial lines passing between the supports 2. In order to obtain maximum stiffness with minimum weight and mass these sections maybe provided with one or more ribs, 42. These ribs may run parallel with each other or at any desired angle. The sections may be of any desired size. In addition to the sections ported in a mid-position between the pole pieces by a spring 17. Thearmature 16 is connected to the cone member A by rod 18,

member 19 and rod 20, as shown in Fig. 4. The rod 18 has flattened portions 18*, 18 near the ends thereof which give flexibility to the rod transversely of its long axis and thus reduces the load on the armature l6. flexibility is in. a plane passing through the rodl8 and the member 19. The rod 20 is connected to the apex of the cone by a clutch device. consisting of a screw threaded member 21 (Fig. 5) having gripping members 22 which are forced into holding position by a nut 23 which screws onto the member 21,

which in turn is securely fastened to the cone member A by a nut 24 which clamps the material of the cone between the nut 24 and a flange 25 on the member- 21. The clutch above described is a very convenient means for connecting the operating rod to the cone. The clutch is easily operated to connect and disconnect the sounding board or sound radiator to and from the operating unit, and at the same time it affords a very firm connection which is not liable to rattle or make other noises. The cone material is reinforced at the apex by the star-shaped metal member 26 on the inside of the cone and the member 27 on the outside. The rod 20 has a dampening cover 28 thereon.

The operating unit is supported inv position on the stand by two members 29 and 30. These members are fastened to the bars 4 of the stand by bolts 31 and 32. v The unit is fastened to the members 29 and 30 by bolts 33 and 34. The openings through the ends of members 29 and 30 and through which bolts 31 and 32 pass are elongated so that the position of the unit may be accurately ad- 'justed relative to the opening in the apex of the cone member A.

The base of the frusto-conical member B is free,since it does not touch any part of the supporting mechanism. I e L I Coils 35 surround the armature 16 and wires 36 and 37 connect at one end with the coils 35 and at the other end with the device producing the sound waves to be translated, such as a radio receiver or other device. The coils are connected in such a sense that their reactions are additive.

Other forms of units maybe used with my sound radiator, but I prefer the unit illustrated.

. The device above described has been successfully used in connection with a radio receiver and produces every faithful reproduction.

While 1 have shown and described one specific embodiment of my invention, It wish it to be understood that my claims are not limited to the specific details shown, as the drawings are merely for the purpose of iliustrating one embodiment of the principles This menace of m invention. Many changes may be made in t e various details without departing from the spirit of my invention. I claim:

1. In a loud speaker, the combination of a support, a cone-shaped sound radiator supported at points intermediate its periphery and apex and vibrating means connected to the apex of the cone. a I

2. In a loud speaker, the combination of a support, a conical sound radiator carried by 4. In a loud speaker, the combination of a conical sound radiator, meansv for flexibly supporting said sound radiator intermediate its periphery and apex and means forimpartingvibratory movement at the apex of the cone and along the axis of the cone.

5. In a loud speaker, the combination of a sound radiator in the form of a shallow cone, means for. flexibly supporting the sound radiator between the base and apex so as to leave the base freeand means connected to the apex of the cone for imparting vibrations thereto.

6. In a loud speaker, the combination of a conical sound radiator, a plurality of radial openings in said sound radiator, flexible members over said openings and means su porting said sound radiator through said flexible members.

7. In a loud speaker, the combination of a support, a cone-shaped sound radiator supported at points intermediate its periphery and apex, a frusto-conical member attached to the periphery of said sound radiator, and vibrating means connected to the apex of the cone.

81.111 a loud speaker, the combination of a support, a conical sound radiator carried by said support, means for flexibly supporting said sound radiator, from said support at points between its peripher' and-apex, a trueto-conical member attache to the periphery of said sound radiator, and means for imparting Vibrations to the apex of said sound radiator to be transformed into sound waves.

9. In a loud speaker, the combination of a support, a conical sound radiator carried by said support, means for flexibly supporting said sound radiator from said support at points between its periphery and apex, an open ended irusto-conical member attached to the periphery of said sound radiator, and

of said sound radiator to be transformed into sound 'waves.

10. In a loud s eaker, the combination of a conical sound ra iator, a plurality of radial openings in said sound radiator, flexible members over said openings, means suflpporting said sound radiator through said exible members, and a frusto-conical member attached to the periphery of said radiator.

11. In a loud speaker, the combination of a conical sound radiator, a plurality of radial openings in said sound radiator, flexible members over said openings means-s11,

orting said sound radiator t rough sald exible members, and a frusto-conical member attached to the periphery of said radiator and extending in an'opposite direction and Wholly supported by said radiator.

LEWIS M. CLEMENT. 

